Dasyuromorphia (Australasian carnivorous marsupials)

Dasyuromorphia > General of Dasyuromorphia

The order Dasyuromorphia includes three families of carnivorousmarsupials in the superfamily Dasyuroidea: theDasyuridae (dasyures), the Myrmecobiidae (numbat), and theThylacinidae (thylacines). The dasyurids and thylacinids aremore closely related to each other than they are to the numbat.

The Australian marsupial radiation produced a numberof other species of carnivorous marsupials in the otherwiseherbivorous order Diprotodontia. These include two genera(Thylacoleo and Wakaleo) and seven species of large, up to 220lb (100 kg), predatory marsupial lions of the family Thylacoleonidae,which are most closely related to koalas andwombats (superfamily Vombatoidea), and an omnivorous(partly flesh-eating) giant rat-kangaroo, in the subfamily Propleopinae,family Hypsiprymnodontidae, superfamily Macropodoidea.

The earliest known carnivorous marsupial in Australia,Djarthia murgonensis, comes from the early Eocene (55 millionyears ago [mya]). The taxonomic affiliation of this andtwo other early carnivorous marsupials is not certain, as keyanatomical features used to clearly identify them to familylevel or even to separate them from the South American marsupialfauna are lacking in the fossils found to date.

The Australiandasyuromorphian and American marsupial taxa arequite distinct but are allied in the possession of many incisors(polyprotodonty) which distinguish them from the herbivorousDiprotodontia.Dasyuromorphians originated in the lateOligocene. The early radiation comprised the very conservativeor “primitive” thylacinids.

Ranging in size from smalldog-sized, 70.5–176.4 oz (2–5 kg) to slightly larger than 65lb (30 kg), thylacines dominated the Australian carnivorousmarsupial fauna until the late Miocene, after which theysteadily declined to two species present in the Pleistocene andonly one persisting until historic times. Dasyurids first appearedin the fossil record in the early to middle Miocene butwere rare until the late Miocene when they diversified andreplaced the thylacine as the dominant marsupial carnivorefauna. Most of the Pleistocene fossil dasyurids are from stilllivingtaxa, although none of the living groups occur earlierthan the Pliocene. Dasyurids are considered to be highly specializedor “derived” dasyuromorphians in terms of their morphology.The numbats are represented by only one livingspecies which appeared in the fossil record as recently as thePleistocene. The numbat is a highly specialised dasyuromorphian,with features of the skull, teeth, and tongue adaptedfor termite feeding.